Chalk holder



FIG. 1 is a perspective view of a chalk holder showing our new design;

FIG. 2 is a front elevational view thereof, the rear elevational view being a mirror image;

FIG. 3 is a right side elevation view thereof, the left side elevation view being a mirror image;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof.

The broken line disclosure in the figures is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a chalk holder, as shown and described. 